Process for treating hair to impart a permanent set thereto



Patented Aug. 21, 1951 PROCESS FOR TREATING HAIR TO IIHPART A PERMANENT SET THERETO Raymond E. Reed, David Tenenbaum, and Marion Den Beste, St. Paul, Minn., assignors to Raymond Laboratories, Inc., St. Paul, Minn., a corporation of Minnesota No Drawing. Application June 4, 1945, Serial No. 597,592

6 Claims.

This invention relates to the treatment of hair, as in the permanent waving thereof.

It is an object of this invention to provide improved processes and hair waving chemicals for permanent molding and/or waving of hair and particularly to provide novel steps in hair molding processes which render the treatment less hazardous to the individual and attain improved results with less chance of failure and a combination of hair waving chemicals for eifecting these processes.

The invention is particularly applicable to permanent hair molding processes of the type involving application to the hair of liquid solutions as the essential treating chemicals and with respect to one step is specifically directed to such processes wherein the liquid solution contains a reducing agent.

Application of such liquid solutions may be made before or after formation of the hair into coils or other desired configuration, although the novel steps hereinafter referred to are particularly advantageous in those processes which involve application of reducing agents to the hair after formation of the hair into coils.

After the tress has thus been coiled, the essential chemical treating solution is applied, as for instance a solution of a reducing agent. The reducing solution may be conveniently applied with a tooth brush or with a hypodermic needle or its equivalent.

As an illustrative example of a highly effective reducing solution, we recommend the following:

Fluid ounces Thioglycolic acid 0.9 Ammonium hydroxide 1.66 Water 13.44

Where such a solution is used, the treated tress is allowed to stand for a period of approximately five to fifteen minutes.

The action of the reducting solution produces a probable conversion of the disulphide linkages of the hair into sulphydryl groups, the ammonium thioglycollate serving as a reducing agent, in accordance with the following equation:

RCH2SSCHz-R 2HSCHz-CO0NH4 Kerstin Ammonium thioglycollate mom-sir s-om-oooNnm Reduced Ammonium keratin dithioglycollate This probable reaction is a reduction reaction so far as the keratin is concerned, but it is accompanied by an oxidation of the ammonium thioglycollate to ammonium dithioglycollate. In accordance with reduction reactions in general, this reaction is apparently reversible and tends to reach an equilibrium. Presence of an excess of ammonium thioglycollate tends to drive the reaction in the direction of keratin reduction. As, however, the concentration of ammonium thioglycollate is steadily reduced as the reaction proceeds, the rate of reduction diminishes. Conversely, the concentration of the product of reaction, ammonium dithioglycollate, steadily increases until the reverse oxidation reaction is brought to a point resulting in an equilibrium.

Some of the reducing agent, however, tends to remain in the hair, and it is generally desirable to remove this by a subsequent oxidation and/or rinsing treatment.

In accordance with the preferred process of our invention, particular oxidizing agents are applied to the tress. These oxidizing agents are especially effective because they tend to rebuild the linkages to a higher level. While such rebuilding may be accomplished by application of excess ammonium dithioglycollate to the coiled tress, tending to drive the reverse oxidation reaction to completion, we have found that economical, stable and otherwise desirable oxidizing agents are the soluble ammonium, alkali and alkaline earth iodates and bromates. Particularly effective agents of this type are sodium and potassium bromate or iodate, which may be applied in five per cent aqueous solution.

oxidizing agents of this type offer many outstanding advantages. Foremost among these is their freedom from tendency to bleach the hair and in this respect they avoid the disastrous effects which may be encountered in the use of peroxides. Furthermore, these oxidizing agents may be applied without particular regard to the alkalinity of the hair. Where peroxide is used, the degrading action thereof on the hair under alkaline conditions is so pronounced that it is necessary to rinse the tresses before the compound can be applied. This rinsing operation is a painful and objectionable experience and involves the expenditure of time. Both the time 3 monium dithioglycollate, thus generating in situ an excess of ammonium dithioglycollate to accelerate oxidation of the reduced keratin. Additionally, these agents act as direct oxidizing agents for the reduced keratin, destroying sulfhydryl groups and forming new linkages.

In addition to previously mentioned advantages of the particular oxidizing agents of this invention in the actual hair-waving operation, they are stable both dry and in solution and the strength of the solution will be maintained. This characteristic is not found in the peroxides and other heretofore used oxidizing agents, solutions of which lose strength, oftentimes unknown to the operator, by reason of repeated or continued opening of the container.

Generally the oxidizing agent should remain in contact with the hair for a period of about twenty minutes. The coil may then be unwound.

Finally the hair may be washed free of chemicals by means of a thorough rinsing operation. Usually a spray with tepid water for a period of five minutes will accomplish a thorough rinsing, and will leave the hair in a permanently waved condition ready for the usual further operations of hair dressing.

Where the coil is unwound before application of the oxidizing agent, the oxidizing agent may be applied as a rinsing solution, in which case the length of rinsing time depends upon the extentof linkage rebuilding necessary but generally ranges from five to twenty minutes.

It will be obvious to those skilled in the art that variations in the reducing and oxidizing steps will yield substantial variations in the results obtained. If very soft waves are desired the various time periods may be reduced; likewise by lengthening the various periods, stronger waves will result.

Further control of the waving process is also possible by varying the strength or alkalinity of the reducing solution. rmbest results we have found that the pH value of the reducing solution a should be above 7 and below 12, with the ideal range lying between 9 and 10.

The various degrees of alkalinity can be readily obtained by adding bases, such as hydroxides of ammonium or the alkali and alkaline earth groups of metals, amines, etc., to the solution r until the desired alkalinity is obtained. Ammonium hydroxide is a preferred material for this purpose.

In general, it will be found that an increase in alkalinity will increase the waving power of the solution. The solution specifically described above will in general produce strong permanent waves. For weaker waves the following solutions, for example, are recommended:

Fluid ounces Thioglycolic acid Ammonium hydroxide 1.5 Water 13.6

Thioglycolic acid 0.9 Ammonium hydroxide 1.33 Water 13.77

used; for instance, the amide of thioglyeolic acid.

hair before coiling or where it is both applied and removed from the hair before coiling, in accordance with processes set forth in our prior application Serial No. 430,474, and whether or not heat be utilized during the waving process and regardless of the particular method for removing the reducing agent. They also find effective use in hair-straightening operations such as are described in our prior co-pending application Serial No. 490,466, filed July 11, 1943, and now abandoned.

This application is a continuation-in-part of our prior co-pending applications Serial No. 430,474, filed February 11, 1942, Patented August 6, 1946, No. 2,405,166 and Serial No. 454,226, filed August 10, 1942, and now abandoned.

We claim:

1. In a process for-treating hair to impart a permanent set thereto, the steps which comprise treating the hair with a reducing agent for keratin and then treating the hair with an oxidizing agent selected from the group consisting of the soluble ammonium, alkali and alkaline earth iodates and bromates.

2. In a process for treating hair to impart a permanent set thereto, the steps which comprise treating the hair with a reducing agent for keratin and then treating the hair with an alkali metal bromate.

3. In a process for treating hair to impart a permanent set thereto, the steps which comprise treating the hair with a reducing agent for keratin and then treating the hair with an alkali metal iodate.

4. The method of neutralizing a reducing solution which has been applied to human hair in the permanent waving thereof comprising applying to hair wet with said reducing solution, a solution of a salt selected from the group consisting of ammonium, alkali and alkali earth metal bromates and iodates.

5. The combination of separate interactable chemical compositions for use sequentially in the cold waving of hair on the human head, the first composition, upon application to .the hair, being adapted to react with the keratin of the hair fiber to relax and soften the same, and the second composition, upon application to the hair wet and softened with the first composition, being adapted to react with and neutralize the first composition and rebuild the hair fiber substantially to its original strength, said first composition consisting essentially of an aqueous solution of a substance selected from the group consisting of a water soluble salt of thioglycolic acid, thiomalic acid, thiosalicylic acid, thiopropionic acid, amides of said thio acids, thioglycerine, and cysteine hydrochloride, and said second chemical composition consisting essentially of a water soluble salt selected from the group consisting of ammonium, alkali and alkali earth metal iodates and bromates.

6. The combination of two interactable chemical compositions maintained normally separated for application in sequence for the permanent waving of human hair, the first composition upon application to the hair being adapted to react with the keratin of the hair fiber to relax and soften the same, and the second composition upon application to the hair wet and softened with the first composition, being adapted to react with and neutralize the first composition and rebuild the hair fiber substantially to its original strength,

said first composition consisting essentially of an aqueous solution of a substance selected from the group consisting of a water soluble salt of thioglycolic acid, thiomalic acid, thiosalicylic acid. thiopropionic acid, amides of said thio acids, thioglycerine, and cysteine hydrochloride, said solution being in suil'icient strength to soften the hair by reacting with the keratin thereof in a short period 01 time not exceeding thirty minutes, and said second chemical composition consisting essentially of a water soluble salt selected from the group consisting of ammonium, alkali and alkali earth metal, iodates and bromates, both of said chemical compositions being quantitatively related to each other so that the second chemical composition in approximately 5% solution will entirely neutralize all of the first composition with which the hair is wetted.

RAYMOND E. REED.

DAVID TEN ENBAUM.

MARION DEN BESTE.

REFERENCES CITED The following references are of record in the file of this patent:

5 UNITED STATES PA'I'ENTS Number Name Date 52,942 Paraf Feb. 27,1866 1,673,022 Sexton June 12, 1928 1,704,767 Shelton Mar. 12, 1929 10 2,061,709 Malone Nov. 24, 1936 2,155,178 Brown Apr. 18, 1939 2,171,885 Michael Sept. 5, 1939 2,201,929 Speakman May 21, 1940 2,225,843 Page Dec. 24, 1940 2,266,111 Wiliat Dec. 16, 1941 2,350,178 Martin May 30, 1944 2,351,718 Speakman June 20, 1944 2,405,166 Reed Aug. 6, 1946 FOREIGN PATENTS Number Country Date 117,071 Australia June 3, 1943 OTHER REFERENCES Windus et al.: "Proof of the Reduction Theory of Unhairing," J. Am. Leather Chem. Assoc., vol. 33, 246-53 (1938); as cited in Chemical Abstracts, vol. 32 (1938), pages 8821-8823.

United States Crt. of Customs and Patent Appeals; Patent Appeal Docket #5241; in re Samuel Grant, Serial No. 372,945, filed August 7, 1945. Pages 35 and 36. 

4. THE METHOD OF NEUTRALIZING A REDUCING SOLUTION WHICH HAS BEEN APPLIED TO HUMAN HAIR IN THE PERMANENT WAVING THEREOF, COMPRISING APPLYING TO HAIR WET WITH SAID REDUCING SOLUTION, A SOLUTION OF A SALT SELECTED FROM THE GROUP CONSISTING OF AMMONIUM, ALKALI AND ALKALI EARTH METAL BROMATES AND IODATES. 